Can a mugho pine be pruned in the winter?
That depends to some extent on why you are pruning.
As a general rule, it's best not to prune a plant in the dead of winter when its bark is frozen unless there is a compelling reason to do so such as storm damage.
If you need to cut back limbs, you are better off pruning in late winter or early spring when the plant is still dormant and not yet showing any signs of putting on new growth.
If you postpone cutting back the limbs until later in the spring or even the summer when the plant is actively growing then you may see a large amount of sap bleeding from the wound. It can be unsightly, but it isn't as alarming as it appears. Bleeding is the pine's way of making sure that invaders don't enter the plant through its injured part so it's doing what needs to be done to protect itself from being colonized.
In late winter, when the plant is still dormant, sap flow will be minimal. If you take off a limb in June, however, the flow can be quite impressive.
If your reason for pruning your pine is to control its size, you can do this by cutting the candles in half when they are fully extended in May or June. Doing it at any other time in the year will result in unsightly ragged tips and can impair the pine's ability to put on new growth in successive years.
If you have any questions or comments, please send them to me at vanessa@gardenmuse.ca.
Posted: November 26, 2010
